Russia on Tuesday launched what it has called its largest ever military drills, with hundreds of thousands of Russian troops taking part along with Chinese soldiers in a massive show of force that has rattled the West.

The week-long war games dubbed "Vostok-2018" (East-2018), "have kicked off" in far eastern Russia and on the Pacific Ocean, the defense ministry said in a statement.

US President Donald Trump on Monday warned Syria against launching an attack on the country's last rebel stronghold with the help of Russia and Iran, saying the offensive could trigger a "human tragedy."

South Korean President Moon Jae-in arrived in Russia Thursday ahead of talks with his Russian counterpart Vladimir Putin, which are expected to focus on economic cooperation and the situation in North Korea.

Russian Foreign Minister Sergei Lavrov Thursday called for dialogue between Israel and Iran following Israeli strikes on Iranian targets in Syria that marked a sharp escalation between the two enemies.